Euclid's one element

In triangle $ABC$ , let $J$ be the centre of the excircle tangent to side $BC$ at $A_1$ and to the extensions of sides $AC$ and $AB$ at $B_1$ and $C_1$ , respectively. Suppose that the lines $A_1B_1$ and $AB$ are perpendicular and intersect at $D$ . Let $E$ be the foot of the perpendicular from $C_1$ to line $DJ$ .

Determine the sum of angles $\angle BEA_1$ and $\angle AEB_1$ in degrees.